Imagine an asteroid were hurtling toward Earth, with a 1-in-1,000 chance of hitting the planet. How would humanity respond to the news, and is there anything we could do about it? A former NASA spacecraft navigator details one possible scenario in a new sci-fi novel.

In “The Darkest Side of Saturn: Odyssey of a Reluctant Prophet of Doom” (iUniverse, 2014), two scientists discover a space rock that could hit Earth in 16 years. The discovery of the asteroid threat pits the scientists against each other, and juxtaposes science against religious fanaticism as humanity attempts to come to terms with the impending doomsday event. If a 2-mile-wide (3.2 kilometers) asteroid collided with Earth, the impact “would almost certainly be a civilization-destroying event,” said author Tony Taylor, of Tempe, Arizona. Taylor is not a spokesman for NASA or an expert on asteroids, but in his career, he has guided spacecraft to every planet in the solar system as a spacecraft navigator at NASA’s Jet Propulsion Laboratory in Pasadena, California, and later at the aerospace consulting firm KinetX Aerospace in Tempe, Arizona. The asteroid that killed the dinosaurs measured at least 6 miles (10 km) across, most scientists agree, but even a 2-mile-wide space rock would likely cause an explosion tens of times larger than that caused by all of the world’s nuclear weapons being detonated at once, Taylor told Live Science. “Hundreds of millions of people would die — if not from direct impact, from starvation and wars,” he said. The book’s title is based on the Voyager spacecraft’s first photos of the night side of Saturn. The novel explores not only the science of detecting a dangerous asteroid on a collision course with the planet, but also the social, political and religious dimensions of such a doomsday event.Handling the news How humanity responds to news of an asteroid threat would depend on the odds that the space rock would hit the planet, and how far in advance humans knew about the potential collision. If the rock were due to strike Earth in just a few months or years, there probably wouldn’t be much controversy about it, and governments would likely work together to try to prepare for the impact, Taylor said. “If you had a revolver with 1,000 chambers and one round, would you play Russian roulette and pull the trigger?” Taylor asked. “Of course you wouldn’t.” But if the chances of the asteroid hitting Earth were less clear-cut, as is the case in Taylor’s novel, then it becomes a question of who believes there’s a risk and who denies it, he said. For instance, initially, scientists might debate how the news should be revealed to the public. In Taylor’s book, this is what happens between the two scientists who discover the asteroid. The main female character, an astronomer, wants to keep the discovery confined to within the scientific community until it can be confirmed unanimously. But her male partner, a spacecraft engineer, wants to reveal it to the public, which he ultimately does behind her back. Once news of the asteroid gets out, it’s easy to imagine how scientific rationalism may become clouded by religious fanaticism, as Taylor suggests in his book. After he makes the announcement, the male scientist gains unwanted attention from a religious fanatic and his followers. The scientist struggles to promote logic over the preacher’s faith-based dogma. Of course, Taylor’s book is fiction, so it’s impossible to know how such an event may play out in reality.Close encounters There are roughly 4,700 potentially hazardous asteroids that measure more than 330 feet (100 meters) across that could pose a danger to Earth, NASA estimates, and 70 percent of these rocks haven’t been identified, Taylor said. The Chelyabinsk meteorite that hit Russia in February 2013 was only about 65 feet (20 m) wide, but the impact produced an explosion equivalent to 500 kilotons of TNT (about 25 times more powerful than the atomic bomb dropped on Hiroshima near the end of World War II), and indirectly injured about 1,500 people. On the same day, another asteroid measuring 150 feet (46 m) across, known as 2012 DA14, came within 17,200 miles (27,680 km) of Earth, passing beneath the orbits of the moon and satellites.

NASA and other organizations are constantly monitoring the skies for these near-Earth objects — asteroids and comets that are nudged by the gravity of other planets into orbits that come within the neighborhood of Earth.

But just having a monitoring program in place isn’t enough, Taylor said. If an asteroid is discovered, the scientists will likely not be the ones with the final say on whether to act or not. “What’s needed is a political endeavor,” he said.